Composition, distribution and sources of polycyclic aromatic hydrocarbons in sediments of the Gulf of Trieste, northern Adriatic Sea

The composition, distribution and the sources of polycyclic aromatic hydroc arbons (PAHs) in the surficial sediments of the Gulf of Trieste were invest igated, To document the spatial PAH input, surficial sediment samples from 17 locations throughout the Gulf were analysed. The total PAH load determin ed in the surficial sediment samples are between 30 and 600 ng g(-1), and w ere the highest in the immediate vicinity of the Port of Trieste, The PAH c ontents decline rapidly with increasing distance from the shore. The ratios of methylphenanthrenes/ phenanthrene and methylpyrene/pyrene are sensitive indicators of the origin of PAH pollution in the Gulf which is mostly pyro litic. The phenanthrene/anthracene ratio mas used to determine the approxim ate location and distance from the source of PAH pollution, while 1-methyl- 7-isopropylphenanthrene (retene) was used as indicator for forest fires, A sediment depth profile indicates a major increase in the PAH concentrations after the First World War. (C) 2001 Elsevier Science Ltd. All rights reser ved.